Types of relationships

Types of relationships

1. one-to-one

   • patient details
   • one record is linked to another table

2. many-to-many

   • they are very rare
   • more than one thing in a table is linked to more than one thing in another table.

3. one-to-many

   • one record will have many links to another table
   • one customer can have many others

4. overcome the problems of storing everything in single tables

5. relationships is built through shared common fields

6. entity relationship diagram is a specified graphic that shows the relationships between entities in a database